This section provides background information related to the present disclosure which is not necessarily prior art.
Wireless application devices, such as laptop computers, cellular phones, etc. are commonly used in wireless operations. And, such use is continuously increasing. Consequently, additional frequency bands are required to accommodate the increased use, and antennas capable of handling the additional different frequency bands are desired.
FIG. 1 illustrates a conventional half-wave dipole antenna 100. The antenna 100 includes a radiator element 102 and a ground element 104. The radiator element 102 and the ground element 104 are connected to, and fed by, a signal feed 106. Each of the radiator element 102 and the ground element 104 has a length of about one quarter of the wavelength (¼λ) of a desired resonant frequency of the antenna. Together the radiator element 102 and the ground element 104 have a combined length of about one half of the wavelength (½λ) 108 of the desired resonant frequency of the antenna.
In order to create a dipole antenna that will radiate in more than one frequency band, one or more additional radiators are sometimes added or tapped to a radiator element of a dipole antenna. Additionally, to reduce the size of the dipole antenna, dipole antenna elements (both radiator elements and ground elements) are sometimes folded, turned, meandered, etc. FIG. 2 illustrates a conventional multi-band folded dipole antenna 200. The antenna 200 includes a first radiator element 202 and a second radiator element 204. Collectively, the first radiator element 202 and the second radiator element 204 form a radiator 205. The antenna 200 also includes a first ground element 206 and a second ground element 208, which collectively form a ground 209. A signal is fed to the antenna through a coaxial cable 210 coupled to the ground 209 and the radiator 205.